The Biostatistics Branch both conducts its own field studies as well as consults and collaborates on field studies lead by other DCEG branches.Field Studies Lead by the Biostatistics BranchBCDDP: Breast cancer detection demonstration project follow-up study (1030) This study follows about 60,000 former participants in the Breast Cancer Demonstration Project (BCDDP). Current analyses include: 1) family history of breast cancer and ovarian cancer risk; 2) reproductive factors, oral contraceptive and hormone therapy use and bladder cancer risk; 3) weight, height, and body mass index and ovarian cancer risk; 4) projecting absolute invasive cancer risk in white women: a model that includes mammographic density; 5) BMI and breast cancer risk; 6) risk factors for histologic types of breast cancer; 7) risk factors according to breast cancer ER/PR status; 8) BMI and mortality; 9) dietary patterns and colorectal cancer risk; 10) dietary pooling project analyses involving cancers of the breast, colon, ovary, and kidney. Black/white PHS study (430)Rates of esophageal and pancreatic cancer are much higher in blacks than whites. We are conducting a study to investigate racial differences with respect to genetic and molecular markers of susceptibility and their interaction with environmental factors among cases from a population-based case-control study. Such markers might be useful for prevention and early detection strategies. Breast cancer: SEER special study (10316)Our long-term objective is to obtain a population-based sample of annotated U.S. breast cancer tissues through collaboration with the SEER Tissue Discard Registries in Iowa, Los Angeles, and Hawaii, and to use these materials to build tissue microarrays (TMAs) to validate discovery-based molecular signatures for different breast cancer subtypes such as luminal, basal, and HER2 phenotypes; providing insights for breast cancer etiology, surveillance, prevention, and treatment. We initiated a demonstration project, using a collection of prepared breast TMAs from SEERs Hawaii Tumor Registry; including n=432 in-situ and invasive breast cancer cases, diagnosed in 1995. Three sets of TMA were obtained for immunohistochemical (IHC) staining: 1) standard IHC 2) Q-Dot technology and 3) the so-called AQUA method, developed by HistoRx Inc. To date, the slides with standard stain have been received and will be scored. Q-Dot and AQUA stains are pending; these stains will not be scored manually. Feasibility study for reducing response bias in studies of childhood cancer research (443)Two focus group sessions with mothers of children with acute lymphoblastic leukemia (ALL) and two with mothers of children with brain tumors were conducted to explore: the optimal time of day, method of administration, and location for the interview; the availability of alternative data sources; the interval between pediatric cancer diagnosis and epidemiological interview; and other features which may affect maternal interview responses. Mothers of children with both types of cancer preferred being interviewed at home during the evening and were willing to provide complete access to their offsprings medical records. Emotional, socioeconomic, and perhaps cultural differences between the groups of mothers were exemplified by the willingness of mothers of children with ALL to participate in epidemiological interviews earlier in their childs treatment course and to provide greater access to maternal reproductive history records compared with mothers of children with brain tumors. Parental concerns about the brain cancer and the difficult treatment course were a key element in their decision to defer participating in epidemiologic interviews for many months after their childs cancer diagnosis. We conclude that the focus group approach can contribute to a broad strategy for improving questionnaires and methods for conducting pediatric cancer epidemiological research.